source3/libsmb/smb_share_modes.c

   1 /*
   2    Samba share mode database library external interface library.
   3    Used by non-Samba products needing access to the Samba share mode db.
   4
   5    Copyright (C) Jeremy Allison 2005 - 2006
   6
   7    sharemodes_procid functions (C) Copyright (C) Volker Lendecke 2005
   8
   9      ** NOTE! The following LGPL license applies to this module only.
  10      ** This does NOT imply that all of Samba is released
  11      ** under the LGPL
  12
  13    This library is free software; you can redistribute it and/or
  14    modify it under the terms of the GNU Lesser General Public
  15    License as published by the Free Software Foundation; either
  16    version 3 of the License, or (at your option) any later version.
  17
  18    This library is distributed in the hope that it will be useful,
  19    but WITHOUT ANY WARRANTY; without even the implied warranty of
  20    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  21    Lesser General Public License for more details.
  22
  23    You should have received a copy of the GNU Lesser General Public
  24    License along with this library; if not, see <http://www.gnu.org/licenses/>.
  25 */
  26
  27 #include "includes.h"
  28 #include "smb_share_modes.h"
  29
  30 /* Database context handle. */
  31 struct smbdb_ctx {
  32         TDB_CONTEXT *smb_tdb;
  33 };
  34
  35 /* Remove the paranoid malloc checker. */
  36 #ifdef malloc
  37 #undef malloc
  38 #endif
  39
  40 int smb_create_share_mode_entry_ex(struct smbdb_ctx *db_ctx, uint64_t dev,
  41                                 uint64_t ino, const struct smb_share_mode_entry *new_entry,
  42                                 const char *sharepath, const char *filename);
  43
  44 static bool sharemodes_procid_equal(const struct server_id *p1, const struct server_id *p2)
  45 {
  46         return (p1->pid == p2->pid);
  47 }
  48
  49 static pid_t sharemodes_procid_to_pid(const struct server_id *proc)
  50 {
  51         return proc->pid;
  52 }
  53
  54 /*
  55  * open/close sharemode database.
  56  */
  57
  58 struct smbdb_ctx *smb_share_mode_db_open(const char *db_path)
  59 {
  60         struct smbdb_ctx *smb_db = (struct smbdb_ctx *)malloc(sizeof(struct smbdb_ctx));
  61
  62         if (!smb_db) {
  63                 return NULL;
  64         }
  65
  66         memset(smb_db, '\0', sizeof(struct smbdb_ctx));
  67
  68         smb_db->smb_tdb = tdb_open(db_path,
  69                                 0, TDB_DEFAULT|TDB_CLEAR_IF_FIRST,
  70                                 O_RDWR|O_CREAT,
  71                                 0644);
  72
  73         if (!smb_db->smb_tdb) {
  74                 free(smb_db);
  75                 return NULL;
  76         }
  77
  78         /* Should check that this is the correct version.... */
  79         return smb_db;
  80 }
  81
  82 /* key and data records in the tdb locking database */
  83 struct locking_key {
  84         SMB_DEV_T dev;
  85         SMB_INO_T inode;
  86 };
  87
  88 int smb_share_mode_db_close(struct smbdb_ctx *db_ctx)
  89 {
  90         int ret = tdb_close(db_ctx->smb_tdb);
  91         free(db_ctx);
  92         return ret;
  93 }
  94
  95 static TDB_DATA get_locking_key(struct locking_key *lk, uint64_t dev,
  96                                 uint64_t ino)
  97 {
  98         TDB_DATA ld;
  99
 100         memset(lk, '\0', sizeof(*lk));
 101         lk->dev = (SMB_DEV_T)dev;
 102         lk->inode = (SMB_INO_T)ino;
 103         ld.dptr = (uint8 *)lk;
 104         ld.dsize = sizeof(*lk);
 105         return ld;
 106 }
 107
 108 /*
 109  * lock/unlock entry in sharemode database.
 110  */
 111
 112 int smb_lock_share_mode_entry(struct smbdb_ctx *db_ctx,
 113                                 uint64_t dev,
 114                                 uint64_t ino)
 115 {
 116         struct locking_key lk;
 117         return tdb_chainlock(db_ctx->smb_tdb, get_locking_key(&lk, dev, ino));
 118 }
 119
 120 int smb_unlock_share_mode_entry(struct smbdb_ctx *db_ctx,
 121                                 uint64_t dev,
 122                                 uint64_t ino)
 123 {
 124         struct locking_key lk;
 125         return tdb_chainunlock(db_ctx->smb_tdb,
 126                                get_locking_key(&lk, dev, ino));
 127 }
 128
 129 /*
 130  * Check if an external smb_share_mode_entry and an internal share_mode entry match.
 131  */
 132
 133 static int share_mode_entry_equal(const struct smb_share_mode_entry *e_entry,
 134                                 const struct share_mode_entry *entry)
 135 {
 136         return (sharemodes_procid_equal(&e_entry->pid, &entry->pid) &&
 137                 e_entry->file_id == (uint32_t)entry->share_file_id &&
 138                 e_entry->open_time.tv_sec == entry->time.tv_sec &&
 139                 e_entry->open_time.tv_usec == entry->time.tv_usec &&
 140                 e_entry->share_access == (uint32_t)entry->share_access &&
 141                 e_entry->access_mask == (uint32_t)entry->access_mask &&
 142                 e_entry->dev == entry->id.devid &&
 143                 e_entry->ino == entry->id.inode);
 144 }
 145
 146 /*
 147  * Create an internal Samba share_mode entry from an external smb_share_mode_entry.
 148  */
 149
 150 static void create_share_mode_entry(struct share_mode_entry *out,
 151                                 const struct smb_share_mode_entry *in)
 152 {
 153         memset(out, '\0', sizeof(struct share_mode_entry));
 154
 155         out->pid = in->pid;
 156         out->share_file_id = (unsigned long)in->file_id;
 157         out->time.tv_sec = in->open_time.tv_sec;
 158         out->time.tv_usec = in->open_time.tv_usec;
 159         out->share_access = in->share_access;
 160         out->access_mask = in->access_mask;
 161         out->id.devid = in->dev;
 162         out->id.inode = in->ino;
 163         out->uid = (uint32)geteuid();
 164         out->flags = 0;
 165 }
 166
 167 /*
 168  * Return the current share mode list for an open file.
 169  * This uses similar (but simplified) logic to locking/locking.c
 170  */
 171
 172 int smb_get_share_mode_entries(struct smbdb_ctx *db_ctx,
 173                                 uint64_t dev,
 174                                 uint64_t ino,
 175                                 struct smb_share_mode_entry **pp_list,
 176                                 unsigned char *p_delete_on_close)
 177 {
 178         struct locking_key lk;
 179         TDB_DATA db_data;
 180         struct smb_share_mode_entry *list = NULL;
 181         int num_share_modes = 0;
 182         struct locking_data *ld = NULL; /* internal samba db state. */
 183         struct share_mode_entry *shares = NULL;
 184         size_t i;
 185         int list_num;
 186
 187         *pp_list = NULL;
 188         *p_delete_on_close = 0;
 189
 190         db_data = tdb_fetch(db_ctx->smb_tdb, get_locking_key(&lk, dev, ino));
 191         if (!db_data.dptr) {
 192                 return 0;
 193         }
 194
 195         ld = (struct locking_data *)db_data.dptr;
 196         num_share_modes = ld->u.s.num_share_mode_entries;
 197
 198         if (!num_share_modes) {
 199                 free(db_data.dptr);
 200                 return 0;
 201         }
 202
 203         list = (struct smb_share_mode_entry *)malloc(sizeof(struct smb_share_mode_entry)*num_share_modes);
 204         if (!list) {
 205                 free(db_data.dptr);
 206                 return -1;
 207         }
 208
 209         memset(list, '\0', num_share_modes * sizeof(struct smb_share_mode_entry));
 210
 211         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 212
 213         list_num = 0;
 214         for (i = 0; i < num_share_modes; i++) {
 215                 struct share_mode_entry *share = &shares[i];
 216                 struct smb_share_mode_entry *sme = &list[list_num];
 217                 struct server_id pid = share->pid;
 218
 219                 /* Check this process really exists. */
 220                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 221                         continue; /* No longer exists. */
 222                 }
 223
 224                 /* Ignore deferred open entries. */
 225                 if (share->op_type == DEFERRED_OPEN_ENTRY) {
 226                         continue;
 227                 }
 228
 229                 /* Copy into the external list. */
 230                 sme->dev = share->id.devid;
 231                 sme->ino = share->id.inode;
 232                 sme->share_access = (uint32_t)share->share_access;
 233                 sme->access_mask = (uint32_t)share->access_mask;
 234                 sme->open_time.tv_sec = share->time.tv_sec;
 235                 sme->open_time.tv_usec = share->time.tv_usec;
 236                 sme->file_id = (uint32_t)share->share_file_id;
 237                 sme->pid = share->pid;
 238                 list_num++;
 239         }
 240
 241         if (list_num == 0) {
 242                 free(db_data.dptr);
 243                 free(list);
 244                 return 0;
 245         }
 246
 247         *p_delete_on_close = ld->u.s.delete_on_close;
 248         *pp_list = list;
 249         free(db_data.dptr);
 250         return list_num;
 251 }
 252
 253 /*
 254  * Create an entry in the Samba share mode db.
 255  */
 256
 257 int smb_create_share_mode_entry_ex(struct smbdb_ctx *db_ctx,
 258                                 uint64_t dev,
 259                                 uint64_t ino,
 260                                 const struct smb_share_mode_entry *new_entry,
 261                                 const char *sharepath, /* Must be absolute utf8 path. */
 262                                 const char *filename) /* Must be relative utf8 path. */
 263 {
 264         TDB_DATA db_data;
 265         struct locking_key lk;
 266         TDB_DATA locking_key =  get_locking_key(&lk, dev, ino);
 267         int orig_num_share_modes = 0;
 268         struct locking_data *ld = NULL; /* internal samba db state. */
 269         struct share_mode_entry *shares = NULL;
 270         uint8 *new_data_p = NULL;
 271         size_t new_data_size = 0;
 272
 273         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 274         if (!db_data.dptr) {
 275                 /* We must create the entry. */
 276                 db_data.dptr = (uint8 *)malloc(
 277                         sizeof(struct locking_data) +
 278                         sizeof(struct share_mode_entry) +
 279                         strlen(sharepath) + 1 +
 280                         strlen(filename) + 1);
 281                 if (!db_data.dptr) {
 282                         return -1;
 283                 }
 284                 ld = (struct locking_data *)db_data.dptr;
 285                 memset(ld, '\0', sizeof(struct locking_data));
 286                 ld->u.s.num_share_mode_entries = 1;
 287                 ld->u.s.delete_on_close = 0;
 288                 ld->u.s.delete_token_size = 0;
 289                 shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 290                 create_share_mode_entry(shares, new_entry);
 291
 292                 memcpy(db_data.dptr + sizeof(struct locking_data) + sizeof(struct share_mode_entry),
 293                         sharepath,
 294                         strlen(sharepath) + 1);
 295                 memcpy(db_data.dptr + sizeof(struct locking_data) + sizeof(struct share_mode_entry) +
 296                         strlen(sharepath) + 1,
 297                         filename,
 298                         strlen(filename) + 1);
 299
 300                 db_data.dsize = sizeof(struct locking_data) + sizeof(struct share_mode_entry) +
 301                                         strlen(sharepath) + 1 +
 302                                         strlen(filename) + 1;
 303                 if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_INSERT) == -1) {
 304                         free(db_data.dptr);
 305                         return -1;
 306                 }
 307                 free(db_data.dptr);
 308                 return 0;
 309         }
 310
 311         /* Entry exists, we must add a new entry. */
 312         new_data_p = (uint8 *)malloc(
 313                 db_data.dsize + sizeof(struct share_mode_entry));
 314         if (!new_data_p) {
 315                 free(db_data.dptr);
 316                 return -1;
 317         }
 318
 319         ld = (struct locking_data *)db_data.dptr;
 320         orig_num_share_modes = ld->u.s.num_share_mode_entries;
 321
 322         /* Copy the original data. */
 323         memcpy(new_data_p, db_data.dptr, sizeof(struct locking_data) + (orig_num_share_modes * sizeof(struct share_mode_entry)));
 324
 325         /* Add in the new share mode */
 326         shares = (struct share_mode_entry *)(new_data_p + sizeof(struct locking_data) +
 327                         (orig_num_share_modes * sizeof(struct share_mode_entry)));
 328
 329         create_share_mode_entry(shares, new_entry);
 330
 331         ld = (struct locking_data *)new_data_p;
 332         ld->u.s.num_share_mode_entries++;
 333
 334         /* Append the original delete_token and filenames. */
 335         memcpy(new_data_p + sizeof(struct locking_data) + (ld->u.s.num_share_mode_entries * sizeof(struct share_mode_entry)),
 336                 db_data.dptr + sizeof(struct locking_data) + (orig_num_share_modes * sizeof(struct share_mode_entry)),
 337                 db_data.dsize - sizeof(struct locking_data) - (orig_num_share_modes * sizeof(struct share_mode_entry)));
 338
 339         new_data_size = db_data.dsize + sizeof(struct share_mode_entry);
 340
 341         free(db_data.dptr);
 342
 343         db_data.dptr = new_data_p;
 344         db_data.dsize = new_data_size;
 345
 346         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 347                 free(db_data.dptr);
 348                 return -1;
 349         }
 350         free(db_data.dptr);
 351         return 0;
 352 }
 353
 354 /*
 355  * Create an entry in the Samba share mode db. Original interface - doesn't
 356  * Distinguish between share path and filename. Fudge this by using a
 357  * sharepath of / and a relative filename of (filename+1).
 358  */
 359
 360 int smb_create_share_mode_entry(struct smbdb_ctx *db_ctx,
 361                                 uint64_t dev,
 362                                 uint64_t ino,
 363                                 const struct smb_share_mode_entry *new_entry,
 364                                 const char *filename) /* Must be absolute utf8 path. */
 365 {
 366         if (*filename != '/') {
 367                 abort();
 368         }
 369         return smb_create_share_mode_entry_ex(db_ctx, dev, ino, new_entry,
 370                                                 "/", &filename[1]);
 371 }
 372
 373 int smb_delete_share_mode_entry(struct smbdb_ctx *db_ctx,
 374                                 uint64_t dev,
 375                                 uint64_t ino,
 376                                 const struct smb_share_mode_entry *del_entry)
 377 {
 378         TDB_DATA db_data;
 379         struct locking_key lk;
 380         TDB_DATA locking_key =  get_locking_key(&lk, dev, ino);
 381         int orig_num_share_modes = 0;
 382         struct locking_data *ld = NULL; /* internal samba db state. */
 383         struct share_mode_entry *shares = NULL;
 384         uint8 *new_data_p = NULL;
 385         size_t remaining_size = 0;
 386         size_t i, num_share_modes;
 387         const uint8 *remaining_ptr = NULL;
 388
 389         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 390         if (!db_data.dptr) {
 391                 return -1; /* Error - missing entry ! */
 392         }
 393
 394         ld = (struct locking_data *)db_data.dptr;
 395         orig_num_share_modes = ld->u.s.num_share_mode_entries;
 396         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 397
 398         if (orig_num_share_modes == 1) {
 399                 /* Only one entry - better be ours... */
 400                 if (!share_mode_entry_equal(del_entry, shares)) {
 401                         /* Error ! We can't delete someone else's entry ! */
 402                         free(db_data.dptr);
 403                         return -1;
 404                 }
 405                 /* It's ours - just remove the entire record. */
 406                 free(db_data.dptr);
 407                 return tdb_delete(db_ctx->smb_tdb, locking_key);
 408         }
 409
 410         /* More than one - allocate a new record minus the one we'll delete. */
 411         new_data_p = (uint8 *)malloc(
 412                 db_data.dsize - sizeof(struct share_mode_entry));
 413         if (!new_data_p) {
 414                 free(db_data.dptr);
 415                 return -1;
 416         }
 417
 418         /* Copy the header. */
 419         memcpy(new_data_p, db_data.dptr, sizeof(struct locking_data));
 420
 421         num_share_modes = 0;
 422         for (i = 0; i < orig_num_share_modes; i++) {
 423                 struct share_mode_entry *share = &shares[i];
 424                 struct server_id pid = share->pid;
 425
 426                 /* Check this process really exists. */
 427                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 428                         continue; /* No longer exists. */
 429                 }
 430
 431                 if (share_mode_entry_equal(del_entry, share)) {
 432                         continue; /* This is our delete taget. */
 433                 }
 434
 435                 memcpy(new_data_p + sizeof(struct locking_data) +
 436                                 (num_share_modes * sizeof(struct share_mode_entry)),
 437                         share, sizeof(struct share_mode_entry) );
 438
 439                 num_share_modes++;
 440         }
 441
 442         if (num_share_modes == 0) {
 443                 /* None left after pruning. Delete record. */
 444                 free(db_data.dptr);
 445                 free(new_data_p);
 446                 return tdb_delete(db_ctx->smb_tdb, locking_key);
 447         }
 448
 449         /* Copy any delete token plus the terminating filenames. */
 450         remaining_ptr = db_data.dptr + sizeof(struct locking_data) + (orig_num_share_modes * sizeof(struct share_mode_entry));
 451         remaining_size = db_data.dsize - (remaining_ptr - db_data.dptr);
 452
 453         memcpy(new_data_p + sizeof(struct locking_data) + (num_share_modes * sizeof(struct share_mode_entry)),
 454                 remaining_ptr,
 455                 remaining_size);
 456
 457         free(db_data.dptr);
 458
 459         db_data.dptr = new_data_p;
 460
 461         /* Re-save smaller record. */
 462         ld = (struct locking_data *)db_data.dptr;
 463         ld->u.s.num_share_mode_entries = num_share_modes;
 464
 465         db_data.dsize = sizeof(struct locking_data) + (num_share_modes * sizeof(struct share_mode_entry)) + remaining_size;
 466
 467         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 468                 free(db_data.dptr);
 469                 return -1;
 470         }
 471         free(db_data.dptr);
 472         return 0;
 473 }
 474
 475 int smb_change_share_mode_entry(struct smbdb_ctx *db_ctx,
 476                                 uint64_t dev,
 477                                 uint64_t ino,
 478                                 const struct smb_share_mode_entry *set_entry,
 479                                 const struct smb_share_mode_entry *new_entry)
 480 {
 481         TDB_DATA db_data;
 482         struct locking_key lk;
 483         TDB_DATA locking_key =  get_locking_key(&lk, dev, ino);
 484         int num_share_modes = 0;
 485         struct locking_data *ld = NULL; /* internal samba db state. */
 486         struct share_mode_entry *shares = NULL;
 487         size_t i;
 488         int found_entry = 0;
 489
 490         db_data = tdb_fetch(db_ctx->smb_tdb, locking_key);
 491         if (!db_data.dptr) {
 492                 return -1; /* Error - missing entry ! */
 493         }
 494
 495         ld = (struct locking_data *)db_data.dptr;
 496         num_share_modes = ld->u.s.num_share_mode_entries;
 497         shares = (struct share_mode_entry *)(db_data.dptr + sizeof(struct locking_data));
 498
 499         for (i = 0; i < num_share_modes; i++) {
 500                 struct share_mode_entry *share = &shares[i];
 501                 struct server_id pid = share->pid;
 502
 503                 /* Check this process really exists. */
 504                 if (kill(sharemodes_procid_to_pid(&pid), 0) == -1 && (errno == ESRCH)) {
 505                         continue; /* No longer exists. */
 506                 }
 507
 508                 if (share_mode_entry_equal(set_entry, share)) {
 509                         create_share_mode_entry(share, new_entry);
 510                         found_entry = 1;
 511                         break;
 512                 }
 513         }
 514
 515         if (!found_entry) {
 516                 free(db_data.dptr);
 517                 return -1;
 518         }
 519
 520         /* Save modified data. */
 521         if (tdb_store(db_ctx->smb_tdb, locking_key, db_data, TDB_REPLACE) == -1) {
 522                 free(db_data.dptr);
 523                 return -1;
 524         }
 525         free(db_data.dptr);
 526         return 0;
 527 }